Charles Ellicott Commentary Psalms 132:17

"There will I make the horn of David to bud: I have ordained a lamp for mine anointed." — Psalms 132:17 (ASV)

Horn of David. —The sprouting or growing horn is an image of young, vigorous life. (See Note, Psalms 75:5.) The Messianic application of this prediction comes out in Zechariah’s song (Luke 1:69).

I have ordained a lamp. —Or, I have trimmed a lamp; the word used in connection with the sacred lights, under the express charge of Aaron and his sons (Exodus 27:21; Leviticus 24:2–3). But with this distinctly sacerdotal allusion we must also combine the special allusion to the Davidic dynasty, according to the promise (1 Kings 11:36): That David my servant may have a light (or, lamp, as here) always before me in Jerusalem.